This invention relates to a laminated packing bag made of heat fusible sheets, preferably a lamination of a polyethylene or polypropylene sheet, an aluminum foil, and a polyester sheet, which are laminated in the order mentioned with the polyethylene or polypropylene sheet innermost, the bag being used to contain juice, milk, sauce or the like of a relatively large quantity suitable for a family or several persons.
In recent years a so-called retort pouch has been known. A retort pouch is a bag packed with a foodstuff wherein the bag is made of a lamination of a polyethylene or polypropylene sheet, an aluminum sheet and a polyester sheet with the polyethylene or polypropylene sheet as the innermost layer. Such pouches containing various types of foodstuffs are sold in markets.
With regard to beverages, the recent tendency is to have packing bags having a relatively large capacity for use by a family unit or a group unit. Usually, the bag is formed by preparing two rectangular laminated sheets of the type described above which are superposed one upon the other and by sealing the four sides of the superposed sheets by fusion, and the bag is filled with such content as juice of a quantity for several persons.
However, when the bag is filled, the four corners of the bag become sharp just like a cushion, so that the bag is not only inconvenient to convey but also has a less pleasing appearance. Moreover, where the volume of the content is large, there is a danger that the seal might rupture and the bag become bulky to carry. Further, where the content is a beverage, it is difficult to dispense.